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Property and Equipment, Net - Schedule of Property and Equipment (Parenthetical) (Detail) - USD ($) $ in Millions | Dec. 31, 2017 | Jan. 01, 2017
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Internal-use software development [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Accumulated amortization for internal-use software development costs | $ 24.2 | $ 21.6

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- Definition For each balance sheet presented, the amount of accumulated amortization for capitalized computer software costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 985 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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